Unable to select the right frame on 2d Blender
from the Blender documentation:
Adjusting the View
The Timeline can be panned by holding MMB, then dragging the area left or right.
You can zoom the Timeline by using Ctrl-MMB, the mouse Wheel, or pressing NumpadMinus and NumpadPlus.
You can also use the scrollbars, located at the bottom or the right of the editor, to pan and zoom the view.
https://docs.blender.org/manual/en/latest/editors/timeline.html#:~:text=The%20Timeline%20can%20be%20panned,pan%20and%20zoom%20the%20view.